Networked Thermostats Help Church Realize Significant Energy Savings

Sat, 2009-08-01 12:00

Comfort maintained in three multipurpose buildings

Located in Cary, N.C., Colonial Baptist Church consists of five multipurpose buildings (Figure 1) that employed a combination of standard and programmable thermostats. In three of the buildings — the 25,500-sq-ft Administration Center, the 25,500-sq-ft Family Center, and the 34,500-sq-ft Worship Center — well-intentioned members of the congregation thought they were helping the facility engineer, Justin Barrett, by modifying schedules and adjusting temperatures. However, they often would press the thermostats' “hold” buttons or forget to set back the thermostats when their event was concluded. In some cases, days would go by before someone noticed the heat or cooling still was running. In the Worship Center, which hosts three Sunday morning services attended by 1,000 church members each, cooling was a challenge during summer, but placing the Worship Center into an energy-saving setback condition at the end of the third service often was overlooked.

With energy prices on the rise, church administrators realized they had to find a way to control their HVAC costs permanently and affordably.

Barrett tried expensive commercial setback thermostats, but they did not allow enough programs for the variety of activities held on the multibuilding campus each day. He contacted building-automation-system companies, but was quoted prices between $60,000 and $70,000, which were far beyond his budget.

“The building-automation systems would certainly be effective, but they had too many features we just didn't need,” Barrett said.

The church wanted an easy-to-use system that would allow complete control and multiple schedules.

While looking through a national church-facilities magazine, Barrett came across an advertisement for the Net/X networked thermostat system from NetworkThermostat.

“I went to their Website, liked what I saw, and the price was right,” Barrett said.

NetworkThermostat offers both wired and wireless choices, which can be combined in one system. For Colonial Baptist Church, Barrett initially selected a traditional wired system. Because a large portion of the buildings had drop-in ceiling tiles, pulling the communications cable was not cumbersome, even though the buildings are nearly 1,000 ft long. The system was completed and running in late summer 2008, dramatically reducing HVAC energy consumption.

“Over $10,300 is a lot to save for our church in just the first four months,” Barrett said. “Considering the system cost, we got an almost immediate payback, and we'll continue to save on energy costs for years to come.”

The savings for each building can be seen in Table 1.

Over the next six months, Colonial Baptist moved walls and reconstructed areas to better meet its ever-changing needs.

“At that point, we knew the wireless would be an amazing help,” Barrett said. “There would be no need to re-run the CAT5 communications cable when we needed to move the thermostats.”

Barrett added wireless backplates and wireless coordinators to the system.

“We simply installed the new modules at the new thermostat locations and used the same network thermostat,” Barrett said. “To finish the installation, we connected the wireless coordinators to the existing network controllers. And to top it off, we had complete backwards compatibility.”

Thermostat schedules were set through downloaded command-center software, which can be loaded onto any PC. No additional computer hardware was required. The church is able to set up to six schedules a day easily and has drag-and-drop capabilities to copy schedules to any other thermostats on the network. Schedules are quickly modified with just a few keystrokes and mouse clicks, allowing both comfort and savings to be maintained as the buildings' activities vary.

Barrett said he particularly likes the lockout/override feature. With the lockout engaged, settings can be changed locally by no more than 3 degrees and for a maximum of either one or three hours. After that, the thermostat automatically returns to its scheduled setting.